Slinger's Thoughts

March 29, 2013

OBD-II Diagnostics – When do you backup.

Filed under: Disaster Recovery, SharePoint — Tags: , , — slingeronline @ 7:56 am

In my last post I spoke about what needed to be backed up. In this one we will address something else that you need to consider in your disaster recovery plan – when.

Ideally you want to create a backup of your content when no one is using it.  Here’s part of why. If you start a backup at 8:00 am on Monday morning, you are probably going to have some unhappy users.  When you start a granular backup, using a 3rd party tool, or the built-in tools like Powershell or Central Administration, the first thing that SharePoint does is lock the Site Collection that is targeted in your backup.  (Doing full farm or database backups does not cause this behavior, but there are other limitations.) While the Site Collection is locked, the users can’t do anything but look at the content in SharePoint.  Anything that would change the contents of any list or library is stopped.  Workflows don’t start. Users cannot update list items or create new documents.  Everything grinds to a halt.  Suddenly SharePoint becomes more like a stuffy museum instead of a petting zoo. (SharePoint was meant to be more like a petting zoo.)  If this happens to your users they will probably not be happy. There is a way around this.  You can opt to not lock sites when you create your backup. This presents another problem that Sean McDonough went into here.

So how do you know when to backup your SharePoint content?  You can assume when no one will be using your SharePoint site and just create backups over the weekend, but this is only hit and miss, and you might be impacting more of your users than you originally thought.  This is why they make diagnostic and performance monitoring tools for SharePoint.

Think of diagnostic tools for SharePoint like the OBD-II sensors in your car. Your car has a myriad of sensors to monitor its performance; fuel sensors, air sensors, and so on. When something is amiss, your car will let you know by a little light on your dashboard. It may not tell you what is wrong, just that something is wrong. When you take the car to a mechanic however, they can pull a code and know exactly what is wrong and what needs to be repaired.  Without a diagnostic tool like this for SharePoint, you may know that something is wrong, but may not be able to determine what. And a diagnostic tool will also let you know if something is going to go wrong before it does, so that you can address it before your end users notice.

So how does a diagnostic tool fit into a DR strategy? You need to know when your SharePoint farm will suffer the least from performing a backup, and when your backups will perform the best.  You don’t want to do a backup when your server is under a high load and there is a lot of traffic on it. It’s not a good idea to guess when an ideal time to perform a backup is. By using tools like performance monitors you can know for sure what kind of impact your backup will have on your end users.

Something else you need to keep in mind about when you backup, is how long your backup will take.  You need to know how long your backup will take to complete so that you can manage your backup within the window that you have determined by your diagnostic tool. The diagnostic tool not only tells you when it is okay to start your backup, but when it should finish by.  Is this really an issue? Absolutely. When I was doing quality assurance testing for Idera’s SharePoint Backup, some of the tests I would perform took days. Not minutes or hours, but days to complete. (This was of course under a very rare and unusual circumstance in a unique environment that you likely don’t have, but it is worth noting.)  Starting a backup on Friday afternoon that doesn’t complete until sometime Wednesday morning that locks up your entire SharePoint farm is not going to make your end users very happy. It is also a good idea to use the performance monitoring tool to see how taxing a backup is on your farm. And to constantly adjust your DR strategy around it. SharePoint is not a static environment. Your end user’s habits change. You need to stay up to speed with what their needs are so that you can accommodate them and work around them.

Fortunately most of the companies that sell DR products for SharePoint also sell performance monitoring tools for SharePoint. There is a reason that those tools exist, and this is one of them.

Create a free website or blog at WordPress.com.